EFFECTS OF A LOADED SPECIMEN WITH CRACK ON THE TRAVELLING OF ULTRASONIC WAVES

Based the theory of elasticity and that of fracture mechanics, the effect of a loaded specimen with crack on the travelling path of ultrasonic wave is studied. By comparing the result of light and ultrasonic waves, it is found that a loaded specimen with crack can be considered as a concave lens (mirror) for light wave and as a convex lens (mirror) for ultrasonic wave.